Media captionRichard Haass was giving evidence to the US Congressional subcommittee of foreign relations

Richard Haass has warned that violence could re-emerge in Northern Ireland if progress is not made in dealing with the legacy of the Troubles.

The former American diplomat, who last year chaired six months of talks on flags, parades and NI's past, made the remarks to a US government committee.

He described the outcome of the talks on New Year's Eve as a disappointment.

Dr Haass said he continues to believe the final blueprint he negotiated with the Stormont parties is viable.

The negotiations broke up without a deal on 31 December last year.

Division

The former diplomat was giving evidence to the US Congressional subcommittee of foreign relations, having been called to provide an update on the state of the Northern Ireland peace process.

Dr Haass told the hearing that without further progress, division and alienation would increase and Northern Ireland could not be held up as an example of peace-building.

"If you walk down parts of Belfast, you are still confronted by concrete barriers separating communities. Upwards of what, 90% of the young people still go to divided, single tradition schools, neighbourhoods are still divided," he said.

"I don't see the society sowing the seeds of its own normalisation, of its own unity, if neighbourhoods and schools are still divided.

"What worries me in that kind of environment - particularly where politics are not shown to be making progress - alienation will continue to fester and violence, I fear, could very well re-emerge as a characteristic of daily life."

Dr Haass also said the recent controversy over secret letters to so-called On the Runs did not justify any party walking away from the ongoing negotiations at Stormont.

The controversy arose when it emerged the UK government sent letters to about 200 republican paramilitary suspects informing them they were not at risk of arrest.

The Ulster Unionist Party pulled out of the talks process over the revelations.

UUP leader, Mike Nesbitt, said his party would no longer take part in leaders' meetings to discuss flags, parades and the legacy of the Troubles in Northern Ireland.

'No amnesty'

Dr Haass told the subcommittee that all he knew about the On the Runs letters had come from the public revelations regarding their existence.

But he said that, as far as he was concerned, the letters did not offer republican fugitives an amnesty.

The diplomat rejected assertions that the final Haass document offering recommendations to the Northern Ireland parties was tilted towards Irish nationalist, rather than unionist, concerns.

Dr Haass warned that without resolving the outstanding issues associated with the legacy of the Troubles, the passage of time would not heal society in Northern Ireland.

He said it was premature to consider Northern Ireland as a "problem solved".

'Deep wound'

Other witnesses at the subcommittee include Geraldine Finucane, the widow of murdered Belfast solicitor Pat Finucane, who was shot dead by loyalist paramilitaries in 1989.

Following allegations that the security forces had colluded in the murder, his family led a long campaign for a full public inquiry.

At Tuesday's hearing, Mrs Finucane pledged to continue her campaign for a full judicial inquiry into her husband's murder.

When she was challenged by one US congressman about whether it was right to continue "picking at the scab" of the Troubles, Mrs Finucane said that, for her, the search for justice was more like a deep wound that needed to be healed.

Civilian shootings

The committee also heard from Belfast man Eugene Devlin, who was shot by the Army in west Belfast in 1972.